The first two parameters are “TOTPOT” and “MEANPOT”, which have similar
physical meanings but are derived in different ways. “TOTPOT” is the total value of the magnetic
free energy, and “MEANPOT” is the average value. Free energy is highly related to the
nonlinear-force-free field. According to previous studies, a great amount of accumulated
magnetic free energy is released within a short time to provide the energy for flares and CMEs
[1]}, [2]}, [3]}, [4]}.
[5]} analyzed the flare in December 2006 by extrapolating its 3D magnetic field
configuration. They calculated the free energy and the shear angle of the AR,
studied the energy release process throughout the evolution of the magnetic field, and
explained the energy release process during a flare. [6]} also
explained the free energy release process by extrapolating the nonlinear-force-free field, and
found that a free energy drop of \(\sim 10^{32}\)  erg happened as the X flare occurred.
In our study, the two SHARP parameters about the free energy are also considered as two of the
most related parameters for flare occurrence.
